The present invention relates to a peridontal probe, that is to say, a dental instrument used for examining whether or not tartar and/or calculus are present in the peridontal cavity or whether there has been any loss of the peridontal attachment tissue.
Known instruments of this type generally comprise a pin-like member which is suitably shaped for insertion into the peridontal cavity of a patient, the pin member being mounted on one end of a handle portion so that the probe can be manipulated.
In most known instruments, the pin member is fixedly attached to, and forms an extension of, the handle portion. However, the pin member is bent intermediate its ends so that the free end portion thereof remote from the handle extends at an angle of substantially 45.degree. to the longitudinal axis of the handle. When used for investigating the peridontal cavities of a patient, the end portion of the pin member is pushed downwardly into the peridontal cavity, between a tooth and the gum, until an increased resistance is felt. This occurs when the pin member strikes against the bottom of the cavity. The depth of the pocket can be readily ascertained if the pin member is provided with graduated markings. A dentist is usually particularly interested in ascertaining how far the cavity extends beyond the boundary between the tooth enamel and the root cementum, from which can be ascertained how much of the peridontal tooth-to-bone attachment fibers in the peridontal space has been lost. Furthermore, such an instrument is suitable for detecting whether tartar has been deposited on the root faces of the tooth in the peridontal cavity.
Ordinarily, the effective portion of the pin member which is used for determining such measurements is of circular cross-section. However, the width of the peridontal cavity is often of the order of a few tenths of a millimeter. Accordingly, it is generally advisable to use an instrument having a flattened end portion so as not to damage the tissue when inserting the probe and also to ensure that the bottom of the peridontal cavity is reached by the pin member. However, probes of such design can only be used for investigating the tongue and cheek faces of the teeth. It is therefore necessary to use another type of instrument having a circular cross-section pin member when probing the interdental regions of the cavities. This is particularly true when probing the rear teeth of a patient because the angle at the corner of the mouth prevents the dentist from holding the handle portion at the correct angle.
The present invention seeks to provide an instrument having a flat portion suitable for determining the above-described measurements but which is suitable for probing the cavities on all sides of the teeth.